Although facts and evidence don’t much matter to the controlling factions on most Capitol Hills these days, it’s never a bad idea to marshall them anyway.

David Moberg’s “The Wrong Target” (In These Times, 10/14/2011) summarizes and highlights the results of a recent study out of the University of California at Berkeley, making clear that public unions are not at all responsible for state budget deficits; neither are public unions responsible for skyrocketing numbers of state jobs (although I don’t see why that’s a bad thing–but that’s just me).

• Public workers have been a steady share of the workforce from 1979 to 2011—averaging 14.2 percent of the entire workforce and ranging from 13.6 to 15.2 percent (slightly increasing typically following a recession simply because private workers disproportionately lost jobs).

• State and local government employment for every thousand residents rose very slightly from 1990 to 2001 (from 60.8 to 64.2 workers for a thousand residents, virtually all in local government), then remained flat through 2009.

• Comparing states with the highest and lowest rates of unionization, the researchers found that from 1990-2009 there were more public employees for every thousand residents in weak- or non-union states than in states densely unionized. Also, there was faster growth in weakly unionized states, especially from 2001 onwards when the ratio of public workers to the population declined in the most unionized states.

• Ultimately, the data seem to show no correlation between union density and public sector employment. (Jacobs suggests some rural, lightly populated and big states that also have few public unions may have a higher ratio to serve a dispersed population.)

• Public worker total compensation has not been growing as a share of state expenditures. Indeed, worker wages and benefit declined as a share of state spending from 1992 to 2002, then remained stable (according to a study from the Center for American Progress).

• As many studies have demonstrated, state and local government workers earn less in wages and benefits than similar private sector workers. Moreover, in recent years private sector labor costs have risen faster than costs in the public sector—a remarkable record considering the widespread wage stagnation and cuts in both pay and benefits in the private sector.

So the next time somebody tells you that public sector unions are bad for the economy, here’s a solid block of evidence to the contrary. We can only hope that evidence starts to matter sooner rather than later.